| 摘要 |
PURPOSE:To provide a resistance measuring method that permits automatic and highly accurate measurement of high resistance values. CONSTITUTION:When a resistor 3 to be measured is connected to a measuring terminal and starting operation is made, a switch 9a is turned ON, and the voltage drop Es generated in a standard resistor 6 is inputted to a voltage measuring device 8. After this is A-D converted, it is inputted to a control circuit 10. When the voltage Eo of a variable DC power source 7 is so set that Es assumes a predetermined value, the circuit 10 controls the switch 9a to OFF and 9b to ON. The value Eo which is the sum of the voltage generated in the resistor 3 and the resistor 6 is supplied to the device 8, and after A-D conversion, it is sent to a memory means 11. In the means 11, the resistance value Rs of the resistor 6 and the voltage Es generated in this are beforehand stored, whereby the resistance value Rx of the resistor 3 is calculated and this is displayed in a display device 13. |
